Method recv

src/socket.cpp:145–193

Future<string> SocketImpl::recv(const Option<ssize_t>& size)
{
  // Extend lifetime by holding onto a reference to ourself!
  auto self = shared_from_this();

  // Default chunk size to attempt to receive when nothing is
  // specified represents roughly 16 pages.
  static const size_t DEFAULT_CHUNK = 16 * os::pagesize();

  const size_t chunk = (size.isNone() || size.get() < 0)
    ? DEFAULT_CHUNK
    : size.get();

  boost::shared_array<char> data(new char[chunk]);
  string buffer;

  return loop(
      None(),
      [=]() {
        return self->recv(data.get(), chunk);
      },
      [=](size_t length) mutable -> ControlFlow<string> {
        if (length == 0) { // EOF.
          // Return everything we've received thus far, a subsequent
          // receive will return an empty string.
          return Break(std::move(buffer));
        }

        buffer.append(data.get(), length);

        if (size.isNone()) {
          // We've been asked just to return any data that we receive!
          return Break(std::move(buffer));
        } else if (size.get() < 0) {
          // We've been asked to receive until EOF so keep receiving
          // since according to the 'length == 0' check above we
          // haven't reached EOF yet.
          return Continue();
        } else if (
            static_cast<string::size_type>(size.get()) > buffer.size()) {
          // We've been asked to receive a particular amount of data and we
          // haven't yet received that much data so keep receiving.
          return Continue();
        }

        // We've received as much data as requested, so return that data!
        return Break(std::move(buffer));
      });
}


Future<Nothing> SocketImpl::send(const string& data)